Summary

Extend the javax.tools API to provide access to javadoc.

Motivation

It is increasingly common to want to invoke tools via an API, as part
of a larger software environment, instead of by exec-ing a new process.
This provides improved performance by avoiding the need to start
additional JVMs, and by providing an API for more type-safe invocation.

Description

The API changes are relatively small, but the implementation behind the
new methods involves some amount of refactoring the existing implementation.
The primary task is to change all existing uses of java.io.File into
corresponding uses of javax.tools.FileObject. Much of this work has
already been done in JDK 7, but the remaining work has had to be deferred
because of a probably dependence on the new NIO API.

Testing

Unit (jtreg) tests will be provided to exercise the new functionality.
There will not be any platform-specific requirements.

Risks and Assumptions

Generally speaking, javadoc is very old code, that has not had much TLC
in a long time. There is a risk that the refactoring will not be as simple
as expected.

Dependences

Up to now, there has been a probable dependence on the new NIO API,
but that has now become available in JDK 7.